With the improvement of living standards of consumers, the requirements of people for the quality and performance of electric toothbrushes are increasingly higher, but because of cost considerations, many products on the market are achieved by traditional micro motors and vibrating rings at present, which have the defects of unstable working frequency, poor vibration effect and dependency on battery voltages to a large extent. Although some special oscillating motors appear on the market, the structures are complicated in general, the consistency is poor and a non-oscillatory effect is liable to occur, thus the special oscillating motors are not suitable for mass promotion.
Chinese patent ZL201320543302.4 discloses a vibrating motor for an electric toothbrush, inductance coils are arranged on a rotor of the vibrating motor, four permanent magnets are respectively installed in the inner cavities of brackets on both sides, and the output rear end of a rotating shaft lever and a rear cover are positioned by a spring positioning pin. The polarity is changed by changing the square wave pulse of the coils to generate an alternate oscillating magnetic field of N, S poles in the coils, in order to drive the rotor to generate a rotational vibration effect. The above-mentioned structure has the defects that, the coils are arranged on the rotor, when the motor is at work, the generated vibration will loosen the coils, and a lead is difficult to arrange. In addition, an enclosure of the motor on the current market is integrated, during installation, a stator is basically installed on the enclosure at first, then the rotor is inserted in the enclosure, and finally the enclosure is sealed to finish the installation. This installation manner is very complicated and is very inconvenient to maintain. When the stator needs to be maintained and replaced, the next operation can only be performed after the rotor is detached.
The current rotor part mainly rotates under the action of a magnetic thrust to generate an angle with the position under the stationary state thereof, then the current direction of the motor changes to change the direction of the magnetic thrust, in this way, the rotor part can reversely rotate in cycles, and the rotor part is located in a reciprocating swing movement. In this case, a condition is generated that after rotating to an angle, the rotor part forms an included angle with the magnetic thrust, when the included angle is quite large, the component force of the magnetic thrust for propelling the rotation of the rotor part is greatly deceased, as a result, it is very difficult to drive the rotor part to rotate. In this case, in a reciprocating swing process, the rotor part is not smooth enough and is bumpy.
Thus a motor is needed on the market, whose rotor part can be located in a smooth reciprocating swing process.